The invention concerns a motor vehicle with an air intake system for drawing in air from the surroundings.
It is necessary for motor vehicles to be able to drive through water, such as flood water, with a particular water level, without water getting into the internal combustion engine through the air intake system. This might otherwise result in engine damage, a so-called water hammer.
In all-terrain vehicles, so-called snorkels are known, by which air can be optionally taken in when driving through water. Such snorkels even allow a crossing of streams. However, these snorkels are separate air intake ducts, which are provided in addition to the air duct typically used and provided in the engine compartment. But such snorkels cannot be used for normal road cars, nor are they needed, since these require instead provisions for water accumulation in the event of heavy rainfall.
One problem which the invention proposes to solve is to provide a motor vehicle with an air intake system for improved travel through water. This problem is solved with a motor vehicle according to embodiments of the invention.
According to an exemplary embodiment of the invention, a motor vehicle is provided, with an air intake system having an air duct, comprising an air inlet for taking in ambient air and an air outlet, wherein the air duct has a curved bent section which is closer to a vehicle running surface upstream than downstream. In the event of a water level of water entering the air duct that is rising parallel to the vehicle running surface, the internal cross section of the bent section is closed by the water before the water can pass the bent section. A plurality of air openings downstream of the bent section are introduced through a wall of the air duct in an outer surface of the air duct pointing away from the vehicle running surface.
The terms “upstream” and “downstream” refer to an intended direction of air flow in the air duct, i.e., “downstream” is the direction inside the air duct from the air inlet to the air outlet, and “upstream” is the reverse direction from the air outlet to the air inlet. The term “vehicle running surface” pertains to a plane which contains the bearing surfaces of the tires of the motor vehicle against the ground. If the vehicle is standing on level ground, then the vehicle running surface corresponds to the surface on which the vehicle is standing. With this embodiment, a solution is provided in which an air duct has alternative air openings by which air can be drawn in to supply the internal combustion engine when the normally used air inlet of the air duct is closed by water on account of driving through water. Furthermore, the air duct is shaped so that a rising water level when driving through water closes the internal cross section of the air duct before the water passes the air duct. This creates a partial vacuum downstream from the closed site, which in turn strengthens the intake of air through the air openings.
According to another embodiment of the invention, the motor vehicle is modified such that the air duct has a highest point, which is a point on the outer surface of the air duct which is furthest away from a vehicle running surface. The air duct has an emergency intake zone which is formed by a wall of the air duct situated on the side away from the vehicle running surface of an imaginary plane running parallel to the vehicle running surface and 1 cm below the highest point. At least some of the air openings are arranged in the emergency intake zone. By placing the air openings in the region of the highest point of the air duct, water entry through the air openings can be better prevented.
According to another embodiment of the invention, all of the air openings are situated in the emergency intake zone.
According to another embodiment of the invention, the bent section has a narrowing of its cross section. Thanks to this narrowing, the air duct has a steep rising shape in the front region, by which water entry can be prevented longer in an event of a rising water level.
According to another embodiment of the invention, the narrowing of the cross section is situated such that the internal cross section area at the cross narrowing of the section is further away from the vehicle running surface than all other internal cross section areas of the bent section.
According to another embodiment of the invention, the motor vehicle moreover comprises an air filter device, which is arranged downstream from the air duct.
According to another sample embodiment of the invention, the outer surface of the air duct is arched outward in a region containing the emergency intake zone.
According to another embodiment of the invention, between the outwardly arched region containing the emergency intake zone and the bent section, the outer surface of the air duct facing away from the vehicle running surface is curved with an opposite direction of curvature to that of the bent section.
According to another embodiment of the invention, the air duct is the sole air duct of the motor vehicle for air supply to an internal combustion engine.
According to another embodiment of the invention, the entire air duct is arranged beneath the engine hood of the motor vehicle.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.